Polyquinazolines and methods for their preparation

ABSTRACT

New polyquinazoline polymers are provided by reacting novel monomers. The polymers incorporate repeat units that have at least one quinazoline nucleus and at least one ether linkage at the quinazoline 2 or 4 position. The quinazoline polymers are prepared by treating a monomer which comprises a quinazolone nucleus having one activated halide group with a base in a dipolar solvent to thereby form the polyquinazoline polymer.

This application is a Divisional application of application Ser. No.08/467,069, Jun. 6, 1995, now U.S. Pat. No. 5,686,560.

FIELD OF THE INVENTION

This invention relates to new methods for preparing polyquinazolinepolymers and to the polymers themselves.

BACKGROUND OF THE INVENTION

Polyquinazoline polymers are useful in a broad range of electronics andmicroelectronics applications, including planarizing dielectric layersin integrated circuit manufacture, passivation layers, as protectivecoatings and potting compounds, as adhesives, as resins for printedwiring board fabrication, as dielectric materials, in coatingapplications for liquid crystal displays, flat panel television, solarwindows, and the like, as fibers, and as high-strength films.

Methods of preparing polyquinazolines by condensation of nitriles withchloroimines are disclosed in U.S. Pat. No. 3,826,783 which issued to B.M. Bloch on Jul. 30, 1974. The polyquinazolines disclosed by Bloch arecharacterized by linkages at the 2 or 4 positions of the quinazolinewhich are either direct, or made through an arylene, alkylene, oralkarylene group.

Many classes of polyheterocycles containing ether linkages are known;the ether linkage providing processability, good thermal, mechanical,and electrical properties, and general ease of synthesis. However,polyquinazolines containing ether linkages at the quinazoline 2, or 4position have not been reported.

It is desired to provide polyquinazolines having ether linkages at thequinazoline 2 or 4 position, derived from relatively low cost startingmaterials, which are processable and have good thermal, mechanical andelectrical properties.

SUMMARY OF THE INVENTION

The present invention provides new and economical methods for formingpolyquinazoline polymers and the polymers themselves.

In a preferred embodiment, the method for forming the polyquinazolinepolymers of the present invention comprises treating a monomercomprising a quinazolone nucleus having one activated halide group witha base in a dipolar solvent to thereby form said polyquinazolinepolymer.

In another embodiment, the method for forming the polyquinazolinepolymers of the present invention comprises the steps of:

a) providing a bis-quinazolone monomer, present as its bis-oxide salt(bis-anion) or in the presence of a base capable of deprotonating thequinazolone groups,

b) providing a second electrophilic monomer prone to nucleophilicsubstitution at two sites, and

c) allowing the bis-quinazolone monomer and the second monomer to reactin a dipolar solvent to thereby form the polyquinazoline polymer.

In yet another embodiment, the method for forming the polyquinazolinepolymers of the present invention comprises providing mixtures ofmonomers having either a quinazolone nucleus having one activated halidegroup, and/or bis-quinazolones, to form polyquinazoline co-polymers.

In another aspect of the present invention, a polyquinazoline polymer isprovided which comprises repeat units comprising at least onequinazoline nucleus and at least one ether linkage.

In yet another aspect of the present invention, multi-chip modules,capacitors, integrated circuits, films, and fibers formed from thepolymers provided in accordance with practice of the present inventionare provided.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the presentinvention will be more fully understood when considered with respect tothe following detailed description, appended claims, and accompanyingdrawings, wherein:

FIG. 1 is a semi-schematic fragmentary cross sectional side view of amulti-chip module provided in accordance with practice of the presentinvention.

FIG. 2 is a semi-schematic exploded perspective view of a capacitorprovided in accordance with the present invention;

FIG. 3 is a semi-schematic cross-sectional side view of an integratedcircuit provided in accordance with practice of the present invention;

FIG. 4 is a semi-schematic perspective view of a multi-filament fiberprovided in accordance with practice of the present invention; and

FIG. 5 is a semi-schematic perspective view of a roll of free-standingfilm provided in accordance with practice of the present invention.

DETAILED DESCRIPTION

This invention is directed to a new class of polyquinazoline polymers,to the monomers which are used for their preparation, to variousproducts formed from the polymers, and to the processes for forming thepolymers.

The polymers provided in accordance with practice of the presentinvention can be formed from a single monomer containing one each of twofunctional group types, typically called an AB monomer, or from twomonomers, each containing two of the same functional groups, typicallycalled type AA and type BB monomers. The terms "type AA monomer," "typeBB monomer," and "type AB monomer" are commonly used for describingmonomers used in condensation polymerization systems. For example, onesuch system is described in U.S. Pat. No. 4,000,187, which is directedto the use of Friedlander reactions to prepare polyquinolines byreacting an aromatic amino carbonyl compound containing two sets ofortho-amino aldehyde or ortho-amino ketone functions (in this case, theAA monomer) with a monomer containing two ketone functions having amethylene group adjacent each function (in this case, the BB monomer).

The polyquinazoline homopolymers of the present invention are preparedeither from two monomers, i.e., from a type AA monomer and a type BBmonomer, or from a single type AB monomer. Polyquinazoline copolymersare prepared from mixtures of two or more type AA monomers with one ormore type BB monomers; or one or more type AB monomers with one or moretype AA, or one or more type BB monomers; or two or more different ABmonomers.

The type AA monomer of the present invention is a bis-quinazolone inwhich each quinazolone nucleus may be deprotonated to form anucleophilic oxy anion. As is known in the art, quinazolones exist intwo isomeric forms, one bearing a proton on the oxygen atom and theother bearing a proton on the nitrogen atom. Treatment of quinazoloneswith a base will abstract this labile proton and produce a quinazoloneanion, where the negative charge is delocalized between the oxygen andnitrogen atoms. In the present invention the quinazolone anion reactsthrough the oxygen atom, and the quinazolone anion therefore reacts as anucleophilic oxy anion. The type BB monomer of the present inventioncomprises a bis-electrophile, in which each electrophilic group has aleaving group that can be displaced by the quinolone anion. The BBmonomers of the present invention are prone to nucleophilic substitutionat two sites. Electrophilic groups are typically aryl halides having anelectron withdrawing group situated ortho or para to the halide.Electron withdrawing groups useful for the practice of the presentinvention include, but are not limited to carbonyl, sulfone, nitro,quinoline, quinazolone, and quinazoline. The polyquinazolines of thepresent invention are formed by allowing the bis-nucleophilic AA monomerto react with the bis-electrophilic BB monomer in a dipolar solventunder conditions where the AA monomer is partially or totallydeprotonated.

The type AB monomers of the present invention contain both nucleophilicand electrophilic groups. The AB monomers are comprised of a quinazolonenucleus containing a single activated halide group. The nucleophilicgroup is the oxy anion of the deprotonated quinazolone. Theelectrophilic group is the haloquinazolone (or halo quinazoline in thegrowing polymer chain) and the leaving group is the activated halide.The AB monomers are reacted in the presence of a base in a dipolarsolvent.

The general structure of AB type monomers provided in accordance withthe present invention is: ##STR1## where one of R₂ and R₄ is OH, and oneof R₂, R₄, R₅, and R₇ is a halide selected from the group consisting ofhalide, ortho-arylhalide, and para-arylhalide, where aryl may beheteroaryl, or substituted aryl. The halide may be F, Cl, Br, or I,preferably, F, or Cl, and most preferably F. The remaining positions onthe quinazolone nucleus may be H or may be substituted with any groups(R)_(n) not interfering with the polymerization reaction, including, butnot limited to, alkyl, aryl, substituted alkyl and aryl, fluoroalkyl,alkoxy, aryloxy, thioether, ketone, aldehyde, C or O bound ester, C or Nbound amide, imide, carboxylic acid, sulfone, cyano (--CN), nitro, andamine.

Non-limiting examples of (AB) monomers useful for practice of thepresent invention are 2-(4-fluorophenyl)-4-quinazolone,2-(2-fluorophenyl)-4-quinazolone, 2-(4-chlorophenyl)-4-quinazolone,2-(2-chlorophenyl)-4-quinazolone, 4-(4-fluorophenyl)-2-quinazolone,4-(2-fluorophenyl)-2-quinazolone, 4-(4-chlorophenyl)-2-quinazolone, and4-(2-chlorophenyl)-2-quinazolone, 5-fluoro-2-quinazolone,7-fluoro-2-quinazolone, 5-fluoro-4-quinazolone, 7-fluoro-4-quinazolone,5-chloro-2-quinazolone, 7-chloro-2-quinazolone, 5-chloro-4-quinazolone,and 7-chloro-4-quinazolone.

The general structure of the bis-quinazolone (AA) monomers useful inaccordance with practice of the present invention which contain twoquinazoline nuclei is given by the following general structural formula:##STR2## where either R₂ and R'₂, or R₄ and R'₄ are OH, and theremaining positions on the quinazolone nuclei may be H or may besubstituted with any groups (R)_(n) not interfering with thepolymerization reaction, including, but not limited to, alkyl, aryl,substituted alkyl and aryl, fluoroalkyl, alkoxy, aryloxy, thioether,ketone, aldehyde, C or O bound ester, C or N bound amide, imide,carboxylic acid, sulfone, cyano (--CN), nitro, and amine; and X is adivalent group selected from the group consisting of nil, alkylene,arylene, and --O--, where arylene may be monocyclic or polycyclic,single, multi-ring, or fused ring divalent aryl groups, including, butnot limited to phenylene, biphenylene, diphenylether, diphenylamine,benzophenone, naphthalenediyl, fluorenediyl, and the like, and whereinnon-limiting examples of alkylene are ethylene (--CH₂ CH₂ --), propylene(--CH₂ CH₂ CH₂ --), 1,4-butylene, and 1,2-propylene.

Non-limiting examples of R groups described above are as follows:

alkyl groups are methyl, ethyl, propyl, isopropyl, tert-butyl,cyclohexyl, stearyl, and docosyl (--CH₂ (CH₂)₂₀ CH₃);

aryl groups are phenyl, biphenyl, naphthyl, anthracenyl, anddiphenylphenyl;

C bound amides are N,N-dimethylaminocarbonyl (--CON(CH₃)₂),N,N-diphenylaminocarbonyl, piperidinecarbonyl (--CONCH₂ CH₂ CH₂ CH₂CH₂), morpholinecarbonyl (--CONCH₂ CH₂ OCH₂ CH₂), andN-methyl-N-phenylaminocarbonyl;

N bound amides are benzoylamino, N-methylacetylamino;

O bound esters are acetyloxy (--OCOCH₃) and benzoyloxy (--OCOC₆ H₅);

C bound esters are methoxycarbonyl (--CO₂ CH₃) and phenoxycarbonyl(--CO₂ C₆ H₅);

alkoxy groups are methoxy, neopentyloxy, and cyclohexyloxy;

aryloxy groups are phenoxy, naphthoxy, and biphenyloxy;

imides are phthalimide, succinimide, and glutarimide;

carboxylic acid groups are --COOH;

fluoroalkyl groups are trifluoromethyl, perfluorobutyl and2,2,2-trifluoroethyl;

ketones are phenylketone (also called benzoyl), naphthylketone(naphthoyl), methylketone (acetyl), ethylketone (propionyl),tert-butylketone (pivaloyl), isobutylketone, trifluoromethylketone(trifluoroacetyl), methoxyethylketone, benzylketone, phenethylketone,2,4,6-trimethylphenylketone, pyridinylketone (nicotinoyl),2-quinolinoketone, and 2-thiopheneylketone; and

aldehyde is --COH.

Non-limiting examples of (AA) monomers useful for practice of thepresent invention are 6,6'-bis-4-quinazolone,6,6'-bis-2-phenyl-4-quinazolone, 6,6'-(1,4-phenylene)-bis-4-quinazolone,6,6'-bis-7, 8-benzo-4-quinazolone (R₇ and R₈ bridging),2,2'-bis-4-quinazolone, 2,2'-(1,4-phenylene)-bis-4-quinazolone,2,2'-(4,4'-biphenylene)-bis-4-quinazolone,2,2'-bis-(1,4-tetramethylene)-4-quinazolone, and 2,2-bis-(4,4'-oxydiphenyl)-4-quinazolone, 6,6'-bis-2-quinazolone,6,6'-bis-4-phenyl-2-quinazolone, 2,2'-(1,3-phenylene)-bis-4-quinazolone,6,6'-bis-7,8-benzo-2-quinazolone (R₇ and R₈ bridging),7,7'-bis-4-quinazolone, 4,4'-(1,4-phenylene)bis-2-quinazolone,4,4'-(4,4'-biphenylene)-bis-2-quinazolone.

The general formula for the bis-electrophilic monomer is W--Y--W, whereW is a halide and Y is a divalent aromatic moiety chosen from

    --Ar--, --Het--, and --Ar'--A--Ar'--

where Ar is an aryl group activate by electron withdrawing groups suchas imide, halide, ketone, and nitro, and --Het-- is heteroaryl, Ar' is adivalent aryl group linked as an ortho-arylene or a para-arylene, and Ais a divalent electron withdrawing group such as carbonyl, sulfone,1,4-dicarbonylbenzene (--CO--C₆ H₄ --CO--), (--CO--C₆ H₄ --O--C₆ H₄--CO--), and the like. A, Ar, and Ar' may be mononuclear, polynuclear,monocyclic, or polycyclic groups. Some specific examples of--Ar'--A--Ar'-- are 4,4'-benzophenone, and 4,4'-phenylsulfone.

Non-limiting examples of bis-electrophilic (BB) monomers useful asmonomers of the present invention are 4,4'-dichlorobenzophenone,4,4'-difluorobenzophenone, 2,2'-difluorobenzophenone,2,2'-dichlorobenzophenone, 4-chlorophenyl sulfone, and 6,6'- -bis2-(4-fluorophenyl)-4-phenylquinoline!: ##STR3## Other bis-electrophilicmonomers will be apparent to one skilled in the art.

The general procedure for forming the polyquinazoline polymers of thepresent invention comprises heating the monomer(s) and a base in asolvent and azeotropically removing water (formed by the reaction of thebase with the hydroxy groups on the AA or AB monomer) The order ofaddition of reactants is not important. The amounts of the monomers usedto form the polymers of the present invention may be determined bystandard formulae known in the art, such as Carother's equation.

In general, (for AA+BB polymerization) while equal molar amounts of AAand BB monomers are normally used, molar ratios other than 1:1 may beused, if desired, to control the MW or end groups. Base is generallyadded in slight molar excess. For the solvent system NMP/toluene thereflux temperature is about 135° C. (the particular temperature dependson the NMP/toluene ratio, with higher ratio giving higher temperature),and water is collected over a six to eighteen hour period. The tolueneor other co-solvent is then removed by distillation and the mixture isheated to greater than about 175° C., (or brought to ref lux, about 202°C. for NMP) and held for 12 to 24 hours (or longer at lowertemperatures), or until the desired polymer MW is achieved. Pressure isnot critical; atmospheric pressure is preferred.

Endcappers may be added at the beginning of the reaction, during thereaction, or near the end of the reaction. The polymer MW may bedetermined as is known in the art by measurement of viscosity or by gelpermeation chromatography (size exclusion chromatography). The reactionis then cooled. The polymer may be recovered from the dope by anytechnique known in the art, including by precipitation with anon-solvent such as alcohol or water. The non-solvent is preferablychosen to be polar in order to remove fluoride salts which are theby-product of the reaction. It is also preferable to filter the polymerdope before precipitation. In some cases it may be desirable to dilutethe dope before filtration or precipitation.

The AB monomer of general formula (1) may be polymerized to givepolymers of the following general structures: ##STR4## where Z isoptionally substituted aryl or heteroaryl, or nil; x is the number ofrepeat units and is preferably from 2 to 1,000,000, more preferably from10 to 10,000, and most preferably from 50 to 1000; the quinazolinegroups may be optionally substituted with any groups (R)_(n) notinterfering with the polymerization reaction, including, but not limitedto, alkyl, aryl, substituted alkyl and aryl, fluoroalkyl, alkoxy,aryloxy, thioether, ketone, aldehyde, C or O bound ester, C or N boundamide, imide, carboxylic acid, sulfone, cyano, nitro, and amine, and nmay be 0 to 4. Examples of R groups of the AB monomers are the same asthose set forth above for the AA monomers.

The AA monomer of general formula (2) may be polymerized with abis-electrophilic type BB monomer to give polymers of the followinggeneral structures: ##STR5## where X, and R are as above, and Y derivesfrom the BB monomer and is as described above.

Exemplary polymers derived from AB monomers are shown below: ##STR6##

Exemplary polymers derived from AA monomers are shown below: ##STR7##

The following examples are illustrative of the present invention but arenot considered limiting thereof in any way.

EXAMPLE 1 Preparation of 4-(4-Fluorophenyl)-2-quinazolone ##STR8##4'-Fluoro-2-aminobenzophenone (164.5 g, 1.20 mol) is heated with urea(72.09 g, 0.500 mol) at 195° C. (1 h) in NMP (500 mL). The solution iscooled and poured into water (2 L). The product is collected byfiltration and dried. The product is purified by recrystallization.EXAMPLE 2 Preparation of 1,4-bis(2,2'-Quinazolonyl)benzene ##STR9##

A mixture of 2-aminobenzamide (6.81 g, 50 mmol), terephthalaldehyde(6.71 g, 50 mmol), sodium bisulfite (15.6 g, 150 mmol) anddimethylacetamide (50 mL) is stirred at 150° C. (4 h). The mixture isthen poured into water (250 mL) and the product is collected byfiltration and dried. The product is purified by recrystallization.

EXAMPLE 3 Preparation of 1,4-bis(2,2'-Quinazolonyl)butane ##STR10##

Anthranilic acid (164.5 g, 1.20 mol) is heated with adipamide (72.09 g,0.500 mol) in dimethylacetamide (500 mL) at 150° C. (4 h). The solutionis cooled and poured into water (2 L). The product is collected byfiltration and dried. The product is purified by recrystallization.

EXAMPLE 4 Preparation of I From 2-(4-Fluorophenyl)-4-quinazolone##STR11##

To a three-necked, 500 mL, round-bottomed flask are added2-(4-fluorophenyl)-4-quinazolone (24.02 g, 100 mmol), anhydrouspotassium carbonate (10.4 g, 75 mmol), NMP (210 mL), and toluene (60mL). The flask is fitted with a mechanical stirring rod set-up, athermometer, and a Dean Stark trap fitted with a condenser and anitrogen inlet valve. A nitrogen atmosphere is established and thereaction is heated to reflux (16 h). The toluene and water by-productare removed from the reaction through the Dean Stark trap and thereaction is further heated to 200° C. (16 h). The reaction mixture isthen cooled to room temperature and diluted with additional NMP (40 mL).The resulting mixture is poured into acetone (1 L) and the product iscollected by filtration. The solid is redissolved in NMP (250 mL) and iscoagulated in water (1 L). The solid is again collected by filtration.The solid is then boiled in hot acetone (1 h), filtered, and dried in avacuum oven at -150° C. (12 H). The letter n defines the number ofrepeat units of the polymer and may be from 2 to 1,000,000, preferablyfrom 10 to 10,000, and most preferably from 50 to 1000.

EXAMPLE 5 Preparation of I From 2-(4-Chlorophenyl)-4-quinazolone##STR12##

To a three-necked, 500 mL, round-bottomed flask is added2-(4-chlorophenyl)-4-quinazolone (25.67 g, 100 mmol), anhydrouspotassium carbonate (10.4 g, 75 mmol), NMP (210 mL), and toluene (60 mL)(the addition of a catalytic amount of a radical scavenger such astetraphenylhydrazine can also be added to the reaction to furtherenhance the properties of the final polymer, see R. S. Mani, B.Zimmerman, A. Bhatnagar, and D. K. Mohanty, Polymer, 1993, 34; 171-181,and references therein). The flask is fitted with a mechanical stirringrod set-up, a thermometer, and a Dean Stark trap fitted with a condenserand a nitrogen inlet valve. A nitrogen atmosphere is established and thereaction is heated to reflux (16 h). The toluene and water by-productare removed from the reaction through the Dean Stark trap and thereaction is further heated to 200° C. (16 h). The reaction mixture isthen cooled to room temperature and diluted with additional NMP (40 mL).The resulting mixture is poured into acetone (1 L) and the product iscollected by filtration. The solid is redissolved in NMP (250 mL) and iscoagulated in water (1 L). The solid is again collected by filtration.The solid is then boiled in hot acetone (1 h), filtered, and dried in avacuum oven at 150° C. (12 H) The letter n defines the number of repeatunits of the polymer and may be from 2 to 1,000,000, preferably from 10to 10,000, and most preferably from 50 to 1000.

EXAMPLE 6 Preparation of II From 4-(4-Fluorophenyl)-2-quinazolone##STR13##

To a three-necked, 500 mL, round-bottomed flask is added4-(4-fluorophenyl)-2-quinazolone (24.02 g, 100 mmol), anhydrouspotassium carbonate (10.4 g, 75 mmol), NMP (210 mL), and toluene (60mL). The flask is fitted with a mechanical stirring rod set-up, athermometer, and a Dean Stark trap fitted with a condenser and anitrogen inlet valve. A nitrogen atmosphere is established and thereaction is heated to reflux (16 h). The toluene and water by-productare removed from the reaction through the Dean Stark trap and thereaction is further heated to 200° C. (16 h). The reaction mixture isthen cooled to room temperature and diluted with additional NMP (40 mL).The resulting mixture is poured into acetone (1 L) and the product iscollected by filtration. The solid is redissolved in NMP (0.250 mL) andis coagulated in water (1 L). The solid is again collected byfiltration. The solid is then boiled in hot acetone (1 h), filtered, anddried in a vacuum oven at 150° C. (12 H). The letter n defines thenumber of repeat units of the polymer and may be from 2 to 1,000,000,preferably from 10 to 10,000, and most preferably from 50 to 1000.

EXAMPLE 7 Preparation of III From 1,4-bis(2,2'-Quinazolonyl)benzene and4,4'-Difluorobenzophenone ##STR14##

To a three-necked, 500 mL, round-bottomed flask is added1,4-bis(2,2'-quinazolonyl)benzene (18.42 g, 50.0 mmol) and4,4'-difluorobenzophenone (10.91 g, 50.0 mmol) , anhydrous potassiumcarbonate (20.7 g, 150 mmol), NMP (210 mL), and toluene (60 mL) . Theflask is fitted with a mechanical stirring rod set-up, a thermometer,and a Dean Stark trap fitted with a condenser and a nitrogen inletvalve. A nitrogen atmosphere is established and the reaction is heatedto ref lux (16 h). The toluene and water by-product are removed from thereaction through the Dean Stark trap and the reaction is further heatedto 200° C. (16 h). The reaction mixture is then cooled to roomtemperature and diluted with additional NMP (40 mL) . The resultingmixture is poured into acetone (1 L) and the product is collected byfiltration. The solid is redissolved in NMP (250 mL) and is coagulatedin water (1 L). The solid is again collected by filtration. The solid isthen boiled in hot acetone (1 h), filtered, and dried in a vacuum ovenat 150° C. (12 H). The letter n defines the number of repeat units ofthe polymer and may be from 2 to 1,000,000, preferably from 10 to10,000, and most preferably from 50 to 1000.

EXAMPLE 8 Preparation of IV From 1,4-bis(2,2'-Quinazolonyl)butane andbis(4-Fluorophenyl)sulfone ##STR15##

To a three-necked, 500 mL, round-bottomed flask is added1,4-bis(2,2'-quinazolonyl)butane (17.32 g, 50.0 mmol) andbis(4-fluorophenyl)sulfone (12.71 g, 50 mmol), anhydrous potassiumcarbonate (20.7 g, 150 mmol), NMP (210 mL), and toluene (60 mL). Theflask is fitted with a mechanical stirring rod set-up, a thermometer,and a Dean Stark trap fitted with a condenser and a nitrogen inletvalve. A nitrogen atmosphere is established and the reaction is heatedto reflux (16 h). The toluene and water by-product are removed from thereaction through the Dean Stark trap and the reaction is further heatedto 200° C. (16 h). The reaction mixture is then cooled to roomtemperature and diluted with additional NMP (40 mL). The resultingmixture is poured into acetone (1 L) and the product is collected byfiltration. The solid is redissolved in NMP (250 mL) and is coagulatedin water (1 L). The solid is again collected by filtration. The solid isthen boiled in hot acetone (1 h), filtered, and dried in a vacuum ovenat 150° C. (12 H). The letter n defines the number of repeat units ofthe polymer and may be from 2 to 1,000,000, preferably from 10 to10,000, and most preferably from 50 to 1000.

The polymer compositions of the present invention are generally usefulin the area of electronics and microelectronics applications because oftheir combination of low dielectric constant, low water uptake, highthermal stability and good solubility. The instant polymers are usefulfor dielectric layers in integrated circuits (IC's) such as planarizers,insulators, passivation layers, encapsulants, adhesives and the like.They are also useful in various wiring board applications, such asprinted wiring boards, flexible wiring boards, tape automated bondingsubstrates, multi-chip modules, dielectrics, other high densityinterconnect devices, and the like. They may also be used in fabricationof electronic components such as capacitors, resistors, discretesemiconductor devices, inductors, or other devices requiring aninsulating layer.

The polymers of the present invention are also useful in electricalapplications such as wire coatings and insulation, insulating lacquers,for fabricating molded connectors, switches, enclosures, insulatingstrips, or the like. Other applications requiring low dielectricconstant and good mechanical properties are coatings applications,especially where high thermal stability and transparency are desired,and insulating applications, including conformal coatings and protectivelayers, potting compounds, and the like. The polymers of the presentinvention are also useful as adhesives, for example as die attachadhesives, optionally with fillers, or laminate adhesives. The polymersof the present invention are also useful as matrix resins forcomposites.

The instant polymers may also be used as free standing films, aslaminated films, fibers, and coatings.

The following examples of applications for the polymers of the presentinvention are intended to be illustrative and are in no way limiting.

Referring to FIG. 1, a semi-schematic cross-sectional side view of amulti-chip module 10, provided in accordance with practice of thepresent invention, is shown. Such multi-chip modules are wiring boardsdesigned to hold several integrated circuit chips (IC's) (not shown)directly without the IC's first being packaged into individual chipcarriers. The multi-chip module is typically (but not necessarily)fabricated using photolithographic techniques similar to those used inIC fabrication. The following procedure outlining multi-chip modulefabrication is illustrative and many variations are known in the art andmay be used with the present invention.

A substrate 12, typically a four- or six-inch silicon or alumina waferhaving a plurality of conductors 13 on its surface, is spin-coated witha layer 14 of a polyquinazoline polymer provided in accordance with thepresent invention. Solvent from the spin-coating process is removed inan oven, and the polyquinazoline layer is cured by heating to a selectedtemperature for a selected period of time as described-above to enhancethe solvent resistance of the polyquinazoline layer. Vias (not shown)are cut through the polymer by any of several techniques, for example,laser drilling or patterning and etching. A layer of metal 16, typicallycopper or aluminum, is deposited and patterned using techniques known inthe art to form metal lines with a portion of the metal 16a extendingthrough the via and contacting the conductors 13. A second layer ofpolyquinazoline 18 provided in accordance with the present invention isspin-coated, dried and cured, completely covering the underlying metal.Vias are cut as above, and a second layer of metal is deposited andpatterned. Additional layers of polymer 20 and metal 22 are added byrepeating the above procedure. In some processes, it may be desirable touse adhesion promoters to enhance adhesion of the polymer to the siliconsubstrate or subsequent layers, or to plate the metal lines withchromium or gold before the application of the polymer.

The polymers of the present invention are also useful as dielectricmaterials in other passive or active discrete electronic components,such as capacitors, resistors, inductors, transformers, diodes,transistors and the like.

Referring to FIG. 2, a semi-schematic exploded view of a capacitor 30 isshown. Dielectric films 32, and 34, comprising a polyquinazoline polymerprovided in accordance with practice of the present invention, insulatemetal foils 36, and 38, which form the plates of the capacitor. Themulti-layer structure is typically wound into a roll 40, and packagedafter providing electrical connections (not shown).

The polymers of the present invention may also be used in coatingapplications such as liquid crystal displays, flat panel TV, lightvalves, solar windows, and the like. The instant polymers are alsouseful in optic and electro-optic applications such as optical waveguides, optical fibers, and non-linear optical devices. Electricalapplications include wire coatings and wire wrap film, protective andanticorrosion coatings, as resin for connectors, housing, switches,plugs, sockets, or other molded electrical components.

The polymers of the present invention are also useful as interlayerdielectrics for integrated circuits. The low dielectric constant andhigh thermal stability are advantageous in interlayer dielectricapplications. The interlayer dielectric separates the signal-carryingmetal layers from each other and/or from the semi-conductor devices ofthe integrated circuit.

Turning to FIG. 3, there is shown a schematic view of an integratedcircuit 42, comprising a semi-conducting device 43, integrated into asilicon wafer 45, metal signal-carrying lines 47, and a polyquinazolinepolymer provided in accordance with practice of the present inventionserving as insulating dielectric layers 44. The polyquinazoline layersare fabricated using techniques commonly known in the art, includingspin-coating followed by curing at elevated temperature.

The polyquinazoline polymers of the present invention are also useful ascoatings where high transmission to visible light is desired. Coatingsfor use in other harsh environments, such as industrial, petrochemical,chemical, are also applications of the instant polymers.

The polyquinazoline polymers of the present invention may also be formedinto fibers, by methods known in the art, such as wet spinning, dryspinning, and extrusion, and subject to further treatments such as hotor cold drawing.

Turning to FIG. 4, there is shown a semi-schematic view of amulti-filament fiber 50, comprising a plurality of mono-filaments 52 ofa polyquinazoline polymer, provided in accordance with the presentinvention.

High strength, thermally stable films, optionally uniaxially oriented,may be prepared from the polyquinazoline polymers of the presentinvention.

Turning to FIG. 5, there is shown a roll 60 of free-standing film 62,formed from a polyquinazoline polymer prepared in accordance withpractice of the present invention.

The above-described fibers and films have various uses, includingtextiles, cord, rope, fibers for use in composites, barrier films,bagging material, electrical and thermal insulation, and release films.

The polymers of the present invention may also be used as matrix resinsfor composites applications.

The above description of preferred embodiments of polyquinazolinepolymers and the monomers useful for forming the polymers are forillustrative purposes. Because of variations which will be apparent tothose skilled in the art, the present invention is not intended to belimited to the particular embodiments described above. The inventiondisclosed herein may suitably be practiced in the absence of anymaterial or composition which is not specifically disclosed herein. Thescope of the invention is defined in the following claims.

What is claimed is:
 1. A method for preparing a polyquinazoline polymercomprising the steps of:a) providing a bis-quinazolone monomer, presentas its bis-oxide salt or in the presence of a base capable ofdeprotonating the quinazolone groups, b) providing a second monomerprone to nucleophilic substitution at two sites, and c) allowing thebis-quinazolone monomer and the second monomer to react in a dipolarsolvent to thereby form the polyquinazoline polymer.
 2. The methodaccording to claim 1, wherein the bis-quinazolone monomer has thefollowing structure: ##STR16## where one of the R₂ and R₄ groups is OHand one of the R'₂ and R'₄ groups is OH, and R is selected independentlyfrom the groups consisting of alkyl, aryl, fluoroalkyl, alkoxy, aryloxy,thioether, ketone, aldehyde, C or O bound ester, C or N bound amide,imide, carboxylic acid, sulfone, cyano, nitro, and amine.
 3. The methodaccording to claim 1, wherein two or more quinazolone monomers are usedto thereby form a polyquinazoline co-polymer.
 4. A polymer comprisingrepeat units having at least one quinazoline nucleus and at least oneether linkage at the quinazoline 2 or 4 position.
 5. The polymer ofclaim 4, wherein the structure of each such repeat unit is ##STR17##wherein R₅, R₆, R₇, and R₈ are independently selected from the group Hand any R.sub.(n) group which does not interfere with the polymerizationreaction, and wherein x is the number of repeat units.
 6. The polymer ofclaim 4, wherein the structure of each such repeat unit is ##STR18##where X is a divalent group selected from the group consisting of nil,alkylene, arylene, and --O--; Y is a divalent group selected from thegroup consisting of:

    --Ar--, --Het--, --Ar'--C(O)--Ar'--, and --Ar'--S(O).sub.2 --Ar'--,

where Ar is an aryl group activated by electron withdrawing groups suchas ketone, nitro, and halide, and --Het-- is heteroaryl, and Ar' isaryl; wherein x is the number of repeat units; and wherein the remainingpositions on the quinazolone nuclei are independently selected from thegroup H or any group R.sub.(n) which does not interfere with thepolymerization reaction, and wherein x is the number of repeat units. 7.The polymer of claim 4, wherein the structure of each such repeat unitis ##STR19## where X is a divalent group selected from the groupconsisting of nil, alkylene, arylene, and --O--; Y is a divalent groupselected from the group consisting of:

    --Ar--, --Het--, --Ar'--C(O)--Ar'--, and --Ar'--S(O).sub.2 --Ar'--,

where Ar is an aryl group activated by electron withdrawing groups suchas ketone, nitro, and halide, and --Het-- is heteroaryl, and Ar' isaryl; wherein x is the number of repeat units; and wherein the remainingpositions on the quinazolone nuclei are independently selected from thegroup H or R.sub.(n), wherein R.sub.(n) is any group not interferingwith the polymerization reaction.
 8. A multi-chip module comprising oneor more layers of dielectric and one or more layers of metal lines,wherein said dielectric is a polyquinazoline polymer of claim
 4. 9. Acapacitor comprising a polyquinazoline polymer provided in accordancewith claim
 4. 10. A fiber comprising a polyquinazoline polymer providedin accordance with claim
 4. 11. A free-standing film comprising apolyquinazoline polymer in accordance with claim
 4. 12. An integratedcircuit comprising insulating dielectric layers comprising the polymerin accordance with claim 4.